Power distribution systems include many electrical devices. Some of the electrical devices have current sensors for sensing current flow in a conductor. For example, power distribution systems generally include circuit breakers, electricity meters, and monitoring equipment. The accuracy of such current sensors is important, since inaccurate current sensing could lead to unnecessarily cutting-off power to a load and discrepancies and inaccuracies in power metering, which are undesirable. Although known sensors provide acceptable results, it would be desirable to even further improve the sensing accuracy of current sensors and to reduce costs.
In addition to high accuracy and low cost, the size of current sensors often is important. For example, if products must be redesigned in order to incorporate a new current sensor, the cost of adding the new current sensor to the product can be very expensive. Preferably, any new current sensor is sized so that the sensor can be easily installed into existing units, such as meters and circuit breakers. Further, since many power system components do not include batteries, the current sensor also should be extendible to provide self power. This generally means that any power required by the current sensing circuit and other electronic components in the breaker unit be provided by the power line being monitored rather than from an external battery.
It would be desirable to provide a current sensor assembly that is accurate and of small size. It would be further desirable to provide a semiconductor current sensor that is responsive to a magnetic field in the plane of a chip.